1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
|
/*
* drivers/mfd/mfd-core.c
*
* core MFD support
* Copyright (c) 2006 Ian Molton
* Copyright (c) 2007,2008 Dmitry Baryshkov
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/acpi.h>
#include <linux/mfd/core.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/module.h>
int mfd_cell_enable(struct platform_device *pdev)
{
const struct mfd_cell *cell = mfd_get_cell(pdev);
int err = 0;
/* only call enable hook if the cell wasn't previously enabled */
if (atomic_inc_return(cell->usage_count) == 1)
err = cell->enable(pdev);
/* if the enable hook failed, decrement counter to allow retries */
if (err)
atomic_dec(cell->usage_count);
return err;
}
EXPORT_SYMBOL(mfd_cell_enable);
int mfd_cell_disable(struct platform_device *pdev)
{
const struct mfd_cell *cell = mfd_get_cell(pdev);
int err = 0;
/* only disable if no other clients are using it */
if (atomic_dec_return(cell->usage_count) == 0)
err = cell->disable(pdev);
/* if the disable hook failed, increment to allow retries */
if (err)
atomic_inc(cell->usage_count);
/* sanity check; did someone call disable too many times? */
WARN_ON(atomic_read(cell->usage_count) < 0);
return err;
}
EXPORT_SYMBOL(mfd_cell_disable);
static int mfd_platform_add_cell(struct platform_device *pdev,
const struct mfd_cell *cell)
{
if (!cell)
return 0;
pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
if (!pdev->mfd_cell)
return -ENOMEM;
return 0;
}
static int mfd_add_device(struct device *parent, int id,
const struct mfd_cell *cell,
struct resource *mem_base,
int irq_base)
{
struct resource *res;
struct platform_device *pdev;
int ret = -ENOMEM;
int r;
pdev = platform_device_alloc(cell->name, id + cell->id);
if (!pdev)
goto fail_alloc;
res = kzalloc(sizeof(*res) * cell->num_resources, GFP_KERNEL);
if (!res)
goto fail_device;
pdev->dev.parent = parent;
if (cell->pdata_size) {
ret = platform_device_add_data(pdev,
cell->platform_data, cell->pdata_size);
if (ret)
goto fail_res;
}
ret = mfd_platform_add_cell(pdev, cell);
if (ret)
goto fail_res;
for (r = 0; r < cell->num_resources; r++) {
res[r].name = cell->resources[r].name;
res[r].flags = cell->resources[r].flags;
/* Find out base to use */
if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
res[r].parent = mem_base;
res[r].start = mem_base->start +
cell->resources[r].start;
res[r].end = mem_base->start +
cell->resources[r].end;
} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
res[r].start = irq_base +
cell->resources[r].start;
res[r].end = irq_base +
cell->resources[r].end;
} else {
res[r].parent = cell->resources[r].parent;
res[r].start = cell->resources[r].start;
res[r].end = cell->resources[r].end;
}
if (!cell->ignore_resource_conflicts) {
ret = acpi_check_resource_conflict(res);
if (ret)
goto fail_res;
}
}
ret = platform_device_add_resources(pdev, res, cell->num_resources);
if (ret)
goto fail_res;
ret = platform_device_add(pdev);
if (ret)
goto fail_res;
if (cell->pm_runtime_no_callbacks)
pm_runtime_no_callbacks(&pdev->dev);
kfree(res);
return 0;
fail_res:
kfree(res);
fail_device:
platform_device_put(pdev);
fail_alloc:
return ret;
}
int mfd_add_devices(struct device *parent, int id,
struct mfd_cell *cells, int n_devs,
struct resource *mem_base,
int irq_base)
{
int i;
int ret = 0;
atomic_t *cnts;
/* initialize reference counting for all cells */
cnts = kcalloc(n_devs, sizeof(*cnts), GFP_KERNEL);
if (!cnts)
return -ENOMEM;
for (i = 0; i < n_devs; i++) {
atomic_set(&cnts[i], 0);
cells[i].usage_count = &cnts[i];
ret = mfd_add_device(parent, id, cells + i, mem_base, irq_base);
if (ret)
break;
}
if (ret)
mfd_remove_devices(parent);
return ret;
}
EXPORT_SYMBOL(mfd_add_devices);
static int mfd_remove_devices_fn(struct device *dev, void *c)
{
struct platform_device *pdev = to_platform_device(dev);
const struct mfd_cell *cell = mfd_get_cell(pdev);
atomic_t **usage_count = c;
/* find the base address of usage_count pointers (for freeing) */
if (!*usage_count || (cell->usage_count < *usage_count))
*usage_count = cell->usage_count;
platform_device_unregister(pdev);
return 0;
}
void mfd_remove_devices(struct device *parent)
{
atomic_t *cnts = NULL;
device_for_each_child(parent, &cnts, mfd_remove_devices_fn);
kfree(cnts);
}
EXPORT_SYMBOL(mfd_remove_devices);
int mfd_clone_cell(const char *cell, const char **clones, size_t n_clones)
{
struct mfd_cell cell_entry;
struct device *dev;
struct platform_device *pdev;
int i;
/* fetch the parent cell's device (should already be registered!) */
dev = bus_find_device_by_name(&platform_bus_type, NULL, cell);
if (!dev) {
printk(KERN_ERR "failed to find device for cell %s\n", cell);
return -ENODEV;
}
pdev = to_platform_device(dev);
memcpy(&cell_entry, mfd_get_cell(pdev), sizeof(cell_entry));
WARN_ON(!cell_entry.enable);
for (i = 0; i < n_clones; i++) {
cell_entry.name = clones[i];
/* don't give up if a single call fails; just report error */
if (mfd_add_device(pdev->dev.parent, -1, &cell_entry, NULL, 0))
dev_err(dev, "failed to create platform device '%s'\n",
clones[i]);
}
return 0;
}
EXPORT_SYMBOL(mfd_clone_cell);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");
|
